From what I have been able to find out (using my daughter's homework) is that "Power Polygons" are any "normal" polygon that can be combined with another "normal" polygon to form another, different looking polygon (a mega-polygon, I guess?)that you can then divide up so you can see the individual "Power Polygon" pieces. Perhaps the name "Power Polygons" is derived from the fact that these polygons have the power to create other polygons. Logically then a "Power Polygon" is, really, just any polygon, just with a new, exciting, and high tech sounding name.
A polygon
It is a seven-sided polygon
polyhedron
It looks like a circle
A chevron. Basically, any polygon with an acute angle whose vertex points to the center of the shape.
A polygon
Like this
the polygon would be a square
A polygon is a plane figure that is closed with straight line segments.
it look like a fifty sided shape
It is a seven-sided polygon
polyhedron
Polygon
The Pentagon.
a triangle.
It is a quadrilateral.
Since there is no need for it to be a regular polygon, it will look like a closed loop.